Refrigerating apparatus



Feb. 4, 1941. H. F. SMITH REFRIGERATING APPARATUS 2 Sheets-Sheet 1Original Filed Aug. 19, 1936 I INVENTOR. flame) F5011!- M-Mm.

Hi6 ATTORNEYS.

Feb. 4, 1941. H. F. SMITH 21,710

REFRIGERATING APPARATUS I Original Filed Aug. 19, 1956 2 Shets-Shget 2#4227 F. Syn-ll.

HIS ATTORNEYS,

Reissued Feb. 4, 1941 UNITED STATES PATENT} OFFICE REFRIGERATINGAPPARATUS Harry F. Smith, Lexington, Ohio, asslgnor to General MotorsCorporation, Dayton, Ohio, a corporation of Delaware Original No.2,085,172, 'dated June 29, 1937, Se-

rial No. 96,823, August 19, 1936. Application for reissue June 20, 1939,Serial No.. 280,130

11 Claims.

preventing condensate water ordinarily flowing normally ineffective andrendered effective by an accumulation of condensate water therein.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

In the drawings: Fig. 1 is a view partly in section and partlydiagrammatic, showing a refrigerating apparatus having the presentinvention embodied therein; Fig. 2 is an enlarged sectional view of apart of the apparatus shown in Fig. 1; and

Fig. 3 is a sectional View taken on the line Of Fig. 2. I K

' Referring to the drawings, for illustrating the present invention, Ihave shown in Fig. 1 thereof a room cooling apparatus housed within acabinet generally represented by the reference character to. Cabinet Illhas a closed refrigerating system mounted therein and the systemincludes an evaporator II having a gaseous refrigerant conduit 12 and aliquid refrigerant conduit l3 connecting same to a refrigerantliquefying and circulating unit. The refrigerant liquefying andcirculating unit includes a compressor II and an electric motor l5operatively connected to the compressor through suitable belt and pulleyconnections. condenser Hi to which conduit I3 is connected and thiscondenser may be cooled in any desirable or well-known manner. In thepresent showing of the apparatus a water flow circuit is employed tocool the condenser l6 and this circuit includes a coil I! mounted in thecompartment motor I8 is mounted in the uppermost portion of cabinet in.This fan I8 is adapted to draw The unit also includes a housing therefrigerant liquefying and circulating unit and is utilized to removeheat of compression from the compartment. The refrigerant liquefying andcirculating unit is preferably mounted upon a base which is suspendinglysupported in the lower compartment of the cabinet. Evaporator H isdisposed horizontally within cabinet Ill intermediate the top and bottomthereof. A fan l8 operatively connected to-an electric air into cabinetI0, through suitable louvres or openings 2| prvided in a side wallthereof, and to force the air over evaporator II where it is 15 chilledor cooled by the refrigerating eifect produced by the evaporator. Thecooled air is caused to flow by fan l8 out of the cabinet or casing l0into the room to be cooled through openings 22 provided in the'top wallof cabinet In. In 0001- ing air passing thereover the evaporator I Iwithdraws moisture from the air and a pan or receptacle 24 is mountedbelow the evaporator to catch moisture dripping therefrom. A pipe 25 isconnected to pan. 24 and extends downwardly therefrom to convey, bygravity flow, the condensate water caught in pan 24 to a suitable drainsource. Liquid refrigerant flowing from the condenser I8 of therefrigerating system into evaporator II is controlled by an expansionvalve 26. Valve 30 '26 has a pipe connection 21 with a thermostatsponsive to pressures in the low side of the re- 40 frigerating system.Switch 3| is interposed in the one power line of the pair 34 and 35thereof leading to motor I5. A thermal overload switch 36 of anysuitable or conventional design is interposed in the power line 35leading to motor l5 and is adapted'to break or open the circuit to themotor when the resistance to flow of electric current through the motorincreases to an abnormal degree to prevent so-called burning of themotor under heavy loads. A magnetic valve 31 is inter- 59 posed in therefrigerant conduit I3 of the closed refrigerating system and iselectrically connected by wires 38 and 38 .to a thermostatic switch 4|and to the power lines 34 and 35. Switch 4| is adapted to be positionedin the room to be expansion valve 26. The switch 4i may alsocontroloperation of motor l9 and consequently fan i8 so that when valve31 is opened the fan creates a circulation of air over the evaporatorand into the room to be cooled. The apparatus thus far described isconventional and .wellknown to those skilledin the art and no further ordetailed description thereof is believed necessary herein.

Since my invention is directed to an'improved apparatus of the typedescribed and pertains to the stopping of the apparatus when certainabnormal or undesirable conditions occur during operation thereof I willnow describe this improved system, While the moisture removed from theair cooled by evaporator ll of the refriger-- ating system is adapted todrip from the evaporator into the pan or receptacle I4 and flow bygravity through pipe 25 to a drain such pipes or drains quite frequentlyget stopped up or become clogged and prevent the flow of watertherethrough. If the refrigerating system is permitted to continueoperation after the drain becomes ineffective for carrying d'rip waterofcondensation away from the cabinet of the refrigerating apparatus, anabnormal condition occurs in that drip water accumulates in the drip panor receptacle 24 and will overflow same. The drip water upon overflowingthe pan 24 is likely to flow on or into the electric motor l of therefrigerant liquei'ying and circulating unit, or into other electricalelements of the apparatus disposed below pan 24, and will causeshort-circuiting or burning of parts of the motor or of the otherelectrical elei to a point near that to cause overflow of the pan,

render the refrigerating system inoperative to ceasecooling of the airso as to indicate to the user or those present in the room being cooledthat some abnormal conditionfhas occured that must be corrected beforethe apparatus will function to produce the desired results. Such asafety device may be placed directly in the pan 24. if

desired, but to simplify the construction of a device of this type andto insure its operation only at the timerequired I'prefer to mount thedevice outside the pan 24. Therefore the device disclosed in the presentdisclosure comprises an elecits upper end soldered to the upper metalwasher 55 and has its other end soldered or otherwise,

tric element generally represented by the reference character 45 andhaving an outer threaded metal terminal 41 insulated by an insulation orthe like plug 48 from a centrally located terminal 49. The plug 4! ishollow and has metal members 5| extending through its side-wail intocontact with the terminal 41. The inner ends of the metal members 5| arebent as at 52 to form a support or abutment for a coil spring 53. Spring53 surrounds a metal rod 54 and is confined within the hollowed outportion of plug 48 between cup-like metal washers 55 the upper one ofwhich is secured under a 'head 56 formed on rod 54. A wire 51 coiledaround rod 54' has suitably secured to the lower washer 55 which lies incontact with the ends 82 of members 5|. It

will therefore be seen that the threaded metal outer terminal 41 isconductively connected with the head 56 of rod 54 through the metalpieces 5|, lower washer 55, wire 51 and the collar surrounding the upperend of rod 54. The enlarged lower end of element 46 has a plate-likewasher of insulating material if secured thereto by a.

metal collar 52 crimped over a shoulder formed on the element 46 toclose the hollowed out or open-ended portion thereof. This collar 62 isprovided with a plurality of depending legs 83 which are utilized forresiliently engaging the outer upper end of pipe 45 to removably securethe element 46 thereto. A pair of vertically disposed plates 54 and 55have an upper shoulder portion 66 thereof extended through theinsulating washer 8i and secured thereto by pins 61. The pair of plates54 and 55 are held in spaced apart relation by a stud 59 which isriveted or otherwise suitably secured thereto intermediate the top andbottom portions thereof. There is a rotatable member .I l below stud 69which is threaded at one of its ends into the plate 65 and has its otherend extended through a suitable opening provided in plate 54. The memberH is split as at I2 for a purpose to be presently described. The lowerend of'rod 54 is bent outwardly and around against itself as at 13 toform an eye portion having a straight shank part 14 extendinghorizontally between the plates 64 and A strip of paper 15, preferablyof a character that is soft and will readily absorb water to thus causesame to lose its tensile strength so as to be easily torn such, forexample, as ordinary newspaper or thin blotting paper, has its one endI6 coiled in overlapping relation around the stud 69 so as to hold thisend against rotation or movement relative to stud 59, The strip of paper15 is then'pass'ed through the eye portion formed by rod 54 while therod is held in a position such as shown in the drawings and the paper istightly stretched between the stud 69 and shank part 14 of rod 54 toseparate the head 55 formed on rod 54 from the terminal 49. The oppositeend H of paper strip 15 is then placed in the slot 12 of member H andmember H is threaded into plate 55. Rotation of member H causes thepaper adjacent the end 11 thereof to be wound around the member II tothereby tightly stretch the paper strip at points intermediate its endsI5 and 11.

The paper strip 15 while being maintained in the stretched positionshown in the drawings holds the rod 54 in a downward position againstthe tension of spring 53 which is compressed between the washers 55.

electrical socket II is threaded upon the threaded terminal 41 ofelement 46 and is provided with terminals 82 and I: having wires 84 andI5 repectively connected to and extending therefrom. Wire 84 isconnected in parallel circuit relation with the motor l5 of therefrigerating system by Another element in the form of a conventional .4

being secured to the power line 34 at a point be- 'termediate itsconnection with the power line 35 and its connection with element orsocket II, to complete the apparatus.

In the normal operation of the apparatus the evaporator H produces arefrigerating eflect and cools air of the room in which the apparatus islocated which air is circulated thereover by operation of fan H. Theswitch 3i controls the starting and stopping of motor I5 to maintain theevaporator between predetermined temperatures. The thermostat switch 4!controls the flow of liquid refrigerant to the expansion valve 26 andconsequently evaporator H in response to temperature conditions existingin the room. Moisture removed from the air during cooling thereof dripsfrom the evaporator l I into the pan or receptacle 24 and this dripwater normally flows to the sewer through the drain pipe 25. In theordinary installation of this type should the drain pipe become stoppedup or clogged with foreign matter the drip water would overflow'the pan24 upon continued operation of the refrigerating system and would flowon or into the motor l5 or on, other electrical elements disposed belowthe pan. The overflow .or drip water may cause the motor or otherelectrical elements to be 'short-circuited and burned beyond repair andin addition, this water flows upon and over the floor of the room inwhich the apparatus is located. However, should water accumulating inthe drip pan 24 of the present apparatus rise to an abnormal height thiswater will also rise the same height in the pipe 45, extending upwardlyfrom the drain pipe 25, and will contact and wet the paper strip 15 ofthe safety device. The water upon soaking the paper 15 destroys itstensile strength and causes same to tear or break. Upon breaking of thepaper strip I5 coil spring 53 in the safety device disclosed forces rod54 upwardly and the head 55 formed thereon therefore moves intoengagement with the terminal 49 in the plug element 46. Obviously theelectric circuit through terminals 49, 83, wire 84, terminals 41, 40 82and wire 85 is completed across the power lines 34 and 35 between thethermal overload protecting switch 36 and motor I5. Current flowing theresistance unit 85 interposed therein and the 4 unit 86 thereby createsan abnormal electrical load which is thrown upon or through the thermaloverload protector 36 and heats same to cause it to trip or open themotor circuit through power lines 34 and 35. Opening of the power lines34 and 35 obviously breaks the circuit to motor I and switch 3| isthereby no longer effective to complete the circuit, thus motor 5 andculating unit is rendered inoperative. The temperature of the room inwhich the apparatus is located will increase above its normal hightemperature limit to thus indicate that the refrigeratlng system isinoperative. By rendering the refrigerating system inoperative in thismanner further condensation of moisture on and flow of drip water fromevaporator I i into pan 24 is prevented and overflow of this pan isthereby eliminated. The system will, of course, remain inoperative untilthe drain pipe 25 has been opened or cleaned out to convey drip waterfrom the apparatus. After the drain pipe 25 has been opened or cleanedout the paper strip I5 in the new strip so that the terminals 41 and 43of the safety device will be maintained in spaced apart relation to keepthe circuit through wires 34 and 35 open. The thermal overload switch 35after having been permitted to cool is reset to complete the electriccircuit therethrough from power lines through this completed circuitmust pass through consequently the refrigerant liquefylng and cirelement45 of the safety device is replaced by a 34 and 35 to motor I! andswitch 3| to again render the apparatus operative.

It is to be understood that in a system where the thermal overloadswitch 35 is not employed the safety device comprising the element 45and SI may be of a modified construction and arrangement whereby thecircuit from the power lines 34 and 35 may be extended through thedevice and the device will normally complete thisthe specificinstallation shown nor to the specific type or construction of safetydevice disclosed as will be apparent from the appended claims.

From the foregoing it will be apparent that I have provided an improvedapparatus of the type adapted to cool and circulate air within a room tobe cooled and that the apparatus by having the'safety device describedincorporated therein overcomes certain difficulties or objectionsencountered in the use and operation of conventional apparatuses of thistype. The safety device of -my improved apparatus is normallyineffective and rendered effective to cause inoperativeness of therefrigerating system automatically by a predetermined accumulation ofdrip water in the water receptacle. The safety device is inexpensive,simple and can be readily reset after the paper strip therein has beentorn or broken by being wetted by the drip water. By incorporating thesafetydevice in the apparatus an improved refrigerating system isprovided in that the device'cooperates with other safety devices andelements in the system to render the system operative at all timesexcept when an abnormal condition occurs which is likely to causeconsid- ,erating system I do not wish to be restricted to erable damageto the system or to the 'buildingin which the system is installed.

While the form of embodiment of the invention as herein disclosed,constitutes a preferred form, it "is to be understood that other formsmight be adopted, all coming Within the scope of the claims whichfollow. l

What is claimed is as follows:

1. In combination, an apparatus including an element which dehumidifiesair, means for circulating a medium through said element to cause saiddehumidification of the air, means for col-' lecting condensate waterfrom said element and for normally conveying the water away from saidapparatus, and normally ineffective means ren-- dered effectiveautomatically in response to a predetermined accumulation of water insaid collecting and conveying means for rendering said lecting andconveying means for rendering said normally ineffective means effective.

culating a medium through said element to cause said dehumidiflcation ofthe air, means for col- 4. In combination, an apparatus including anelement which dehumidifies air, means for circulating a medium throughsaid element to cause said dehumidification of the air, means iorcollecting condensate water from said element and for normally conveyingthe water away from saidapparatus, said circulating means including amotor and an electric circuit leading thereto, means interposed in saidelectric circuit for controlling operation of said motor, a switchinterposed in said electric circuit between said control means and saidmotor, and means responsive to a predetermined accumulation of water insaid collecting and conveying means for actuating said switch to rendersaid motor inoperative.

5. In combination, "an apparatus including an element which dehumidiflesair, meansv for circulating a medium through said element to cause saiddehumiditlcation of the air, means for collecting condensate water fromsaid element and for normally conveying the water away from saidapparatus, said circulating means including a motor and an electriccircuit leading I thereto, means interposed in said electric circuit forcontrolling operation of said motor,a normally closed thermal overloadmeans interposed in said electric circuit, a switch interposed in saidelectric circuit between said thermal overload means and said motor, andmeans responsive to a predetermined accumulation of water in saidcollecting and conveying means for actuating said switch to causeopening of said normally closed thermal overload means to thereby rendersaid motor inoperative.

6. In combination, an apparatus including an element which dehumidifiesair, means for circulating a medium through said element to cause saiddehumidiflcation of the air, means for collecting condensate water fromsaid element and for normally conveying the water away from saidapparatus, said circulating -means including a motor and an electriccircuit leading thereto, means interposed in said electric circuit forcontrolling operation of said motor, a normally closed thermal overloadmeans interposed in said electric circuit, a normally open switchinterposed in said electric circuit between said thermal overload meansand said motor, and means responsive to a predetermined accumulation ofwaterin said collecting and conveying means for closing said normallyopen switch to cause opening of said normally closed thermal overloadmeans to thereby render said motor inoperative.

7. In combination, an apparatus including an element which dehumidinesair', means for circulating a medium through said element to cause saiddehumidiflcation ofthe air, means for col- 3. In combination, anapparatus including an element which dehumidifies air, means forcirmeans interposed in said electric circuit for controlling operationof said motor, a normally closed thermal overload means interposed insaid elecfltric circuit, a switch interposed in said electric circuitbetween said thermal overload means and said motor, a resistance unitinterposed in said electric circuit between said switch and said thermaloverload means, and means responsive to a predetermined accumulation ofwater in said collecting and conveying means for actuating said switchto energize said resistance unit and cause opening'ot said normallyclosed thermal overload means to thereby render said motor inoperativel8. In combination, an apparatus including an element which dehumidifiesair, means for circulating a medium through said element to cause saiddehumidiflcation of the air, means for collecting condensate water fromsaid element and for normally conveying the water away from saidapparatus, saidcirculating means including a motor and an electriccircuit leading thereto, means interposed in said electric circuit forcontrolling operation of said motor, a normally closed thermal overloadmeans interposed in said electric circuit, a normally open switchinterposed in said electric circuit between said thermal overload meansand said motor, a resistance unit interposed in said electric circuitbetween' said switch and said, thermal overload means, and meansresponsive to a predetermined accumulation of water in said collectingand conveying means for closing said normally open switch to energizesaid resistance unit and cause opening 01 said normally closed thermaloverload means to thereby render said motor inoperative.

9. In combination, an apparatus including an element which dehumidifiesair, means for cir culating a, medium through said element to cause saiddehumidiflcati'on of th air, means for collecting condensate water fromsaid element and for normally conveying the water away from saidapparatus, and normally 'inefiective means rendered efiectiveautomatically in response to a predetermined accumulation of water insaid collecting and conveying means for preventing further accumulationof condensate water in said collecting and conveying means above said.predetermined accumulated amount thereof.

10. In combination, an apparatus including an element which dehumidifiesair, means for circu-- lating a medium through said element to causesaid dehumidiflcation of the air, means for collecting condensate'waterfrom said element and for normally conveying the water away from saidapparatus, and normally ineffective means 1 means above saidpredetermined accumulated amount thereof.

1-1.. An air conditioning apparatus comprising an air cooling unit, arefrigerant circulating unit connected to said cooling unit, collectingmeans for collecting condensate from said air cooling unit, and meanspreventing the operation of said circulating unit upon the accumulationof a predetermined amount of liquid in said collecting 'means.

HARRY F. SMITH.

55 rendered effective automaticallylin response to

